Inspections en service des soudures longitudinales

Inspection Challenges

Inspection of pipe seam welds requires a volumetric NDE inspection method. Traditionally, radiography (RT) is used for manufacturing inspection, but this technology has several drawbacks. In terms of inspection capability, RT is insensitive to mis-oriented planar defects, and doesn’t provide any through-wall sizing capability. There is no immediate feedback to the welders, and RT is disruptive to other activities on the site. With safety regulations getting more and more severe worldwide, the use of radiography is being drastically restricted. Additionally, the cylindrical geometry of long seam welds requires specific attention with regards to examination coverage and flaw positioning.

Recommended Solution & Advantages:

An integrated TOFD and Phased Array system is the optimal solution for this type of application delivering significant advantages.

Encoded weld examination using a combination of PA UT and TOFD is a reliable and efficient alternative for RT. It provides excellent inspection capability, with permanent records. In addition, the overall duration of the inspection process is drastically reduced, and ultrasonic examination provides immediate feedback regarding the welding process. The same ultrasonic techniques are also very suitable for in-service inspections.

Zetec proposes a complete inspection solution to deal dealing with a variety of pipe diameters and wall-thicknesses. The Weld Crawler is a dedicated scanner for long seam welds that allows simultaneous deployment of PA UT and TOFD techniques, in combination with a powerful and portable data acquisition unit.